Grinding attachment.



A. BLOM.

GRINDING ATTACHMENT.

APPLICATION FILED FEB. 25, 1914.

Patented Nov. 24, 1914.

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Quota w pnolo-Lrrnu ALEXANDER BLOM, OF READING, PENNSYLVANIA.

GRINDING ATTACHMENT.

Specification of Letters Patent.

Patented Nov. 24, 1914.

Application filed February 25, 1914. Serial No. 820,823.

To all whom it may concern:

Be it known that I, ALEXANDER BLoM, a citizen of the United States, residing at Reading, in the county of Berks and State of Pennsylvania, have invented certain new and useful Improvements in Grinding At tachments, of which the following is a specification.

My invention relates to attachments for sewing machines or the like, and more particularly to grinding and polishing devices.

My object is to provide a simple and inexpensive abrasive device that may be quickly and easily applied to the balance wheel of the machine for polishing or grinding household articles or tools.

The invention consists of a flanged metal ring provided with an outer surface of abrasive material, and adapted to closely fit over and frictionally engage the balance wheel, as fully described in connection with the accompanying drawing, and the novel features being particularly set forth in the subjoined claim.

Figure 1 is a sectional elevation, on the line 11 of Fig. 2, of a grinder ring embodying my invention and showing its application to the balance wheel of a sewing machine. Fig. 2 is an inside face view of the ring, and Fig. 3 an edge view thereof, partly in section.

In the drawings 1 represents the main shaft of a sewing machine, 2 the balance or fly wheel therefor, and 3 the drive pulley, driven by a drive belt 4 connected to the usual drive wheel not shown. balance wheel I frictionally mount my grinding ring, which, when the wheel is driven, provides a convenient and useful grinder for polishing or sharpening household articles.

My grinder ring attachment comprises a flanged sheet metal ring, the flat peripheral portion 5 of which is adapted to closely fit over the balance wheel, and the flange portion of which contacts with a side face of the wheel. This flange is inwardly curved as shown so as to provide a flat radial portion 6 at the edge of the peripheral portion 5, and a wheel contacting radial portion 7, set inward from said radial portion 6, and connected by a curved relatively yielding portion 8. This construction of the ring Upon this provides a relative yield of the peripheral and flange portions and insures a better frictional grip upon the balance wheel, and the inset radial portion 7 of the flange provides for extending the peripheral portion 5 beyond the wheel 2 to give a broader grinder surface than could be obtained with a straight flange. To give a better frictional grip upon the wheel 2 and to prevent scratching or injuring the enameled surface thereof I cover this flanged metallic ring with a fabric covering .9 of flannel, felt or the like, secured to said ring by glue or paste and completely covering both the peripheral and flange portions thereof. Upon the outer peripheral surface of this covered ring I apply an abrasive substance 10 as emery or sand to form a grinding or polishing surface, and I also preferably apply this abrasive substance to the fabric covering the outer radial portion 6 of the flange so as to form a side grinding portion 11.

My invention is simple, cheap and eflective and readily applied to the balance wheel by merely frictionally forcing the same thereon, the fabric covering insuring an adequate grip against slippage and the inset contacting portion 7 of the flange, not only giving additional friction against slippage but permitting a broader grinding surface of the peripheral ortion 5. This grinder ring may be applie to both flat and round-surface balance wheels, and in. the latter case the flange insures against any tilting tendency of the ring upon the wheel.

What I claim is The herein described grinding attachment for sewing machine balance wheels, consisting of a fabric-covered sheet-metal ring having a right-angular flange the inneredge portion of which is set-in under the peripheral portion of the ring; the outer portions of said ring and flange being faced with abrasive material and said set-in flange portion being adapted to cooperate with the peripheral portion of the ring in yieldingly engaging the balance wheel.

In testimony whereof I aflix my signature in presence of two witnesses.

ALEXANDER BLOM. Witnesses:

C. P. Bownns, D. M. STEWART.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. G. 

